Automatic draft-controller.



No. 880,924. PATENTED MAR. 3, 1908.

e. E, SGHUETZ. AUTOMATIG DRAFT CONTROLLER.

Arrmoumn En-En MAY 24. 1907.

WITNESSES -INVEN7'0H cnoncn E. SOHUETZ; OF WEST HOBOKEN, NEW- Jn'a"AUTOMATIC DRAFT-CONTROLLER.

No. ssopee.

nection with the damperor other dra t-con-- trolling device of theboiler, to controlthe fire so as to "maintain the temperature orpressure in the boiler at or near. a predetermined point. In suchmechanisms, asusually constructed,- thedraft-controlling device isconstantly under the control of the automatic mechanism and ismaintained inmore or less operative position at all temperaturesonpressures except the lowest, bemg moved to reduce the raft graduallyin proportion as the temperature or pressure a 'proaches thepredetermined maximum.- This" arrangement is'defectiv'e for the reason.

that ita'ffords no provision forebring'ing the tem erature or ressure inthe boiler as quic ly as possi le to the desired, point when, throu hany cause, such as a'sudden increase in dlamand onfthe boiler, or anundue slackening in the fire, the temperature "or pressure has fallenconsiderably .belo'w suc point. To. attain such a result it'isnecessaryto use the full draft until thev teem; perature or pressurehasrisen to orsubstam tially to the proper point, and then to reduce thedraftimmediately to the amount re,-

quired .to maintain this temperature or'pressure. v Theobje ct' of theproduce a draft-controllin mechanism. .in

which this result is attaine and to-this end" the invention comprises a'mechanism arranged tomaintainthe draft-controlling device with which,it is connected in-positio'n to i give the full draft until thetemperature or pressure in the boiler has risen to, or substan tially tothe redetermined point, and then S0 to move the draft-controlling devicequickly" to a position to substantially reduce the draft,'so that thefire, after raising the tem 'perature or pressure as quickly aspossible, may, upon the attainment of 'the desired temperature orpressure, he at once checked Specification or Lett'ers Pat ent:

- Application 111m May 24, 1907. Serial No. 375,400. i i

present invention is to PATENT sufficiently to prevent the-temperatmge[on pressure rising substantiallygab oyethiapo Another object-of theinventionis to vide an automatic draft-centre anism with an alarm whiching when, for any reason,- the ,perat p themechanism is madQQ-HQQJQQ PFQdue rise in the temperature onpressnfe" d f: to this end theinvention-comprise a controlling mechanism, provided alarm whichoperates; autpmat' the draft-controlling "cl .draft-controllin mech V,has been move .to aposition predetermined maximum :dra-f red eifected'.

invention illustrated drawing's, ,and will theigeafter invention inclaims. Figure ,1 of the 6m rm. stant y to rotate the da per positionindicated in the drawings closed position at atright angle; reto.Such-movement is controlled; newer r hy a chain 7 connectedwith, auwar'dlyextending arm 8 on-the' rod Q T m oo passes around pulleysgfland-"l'l ta'ched to the ofi'setend" 11 of I g lever 12. Thecontrolling le' is wot u at 13 to a frame 14 mtanted on the bbller, anda plunger 15 connects the lever with an *iplastic expansible pressurechamber 16 of d'rdinary form, connected, through a pipe 17, with theboiler. p The lever is provided with a (weight 29,1

and thetendency of the weight and the lever no i a detent rests on t isto descend and, by pullin on the chain 7 to move the damper to wice-open position, but this tendency is resisted by the spring 6,

assisted by the pressure chamber 16 in pro-' boi er, the balanceofiorces will be such as to hold the damper in position to maintain thefire' at the proper point to maintain such pressure in the boiler. i Themechanism for holding the damper in wide-o en position comprises a.detent 18 pivote at 19 on an upright 20 and rovided with a notch 21which engages an retains the upper end of the arm 8 when the damper isin wideopen ]position. The end of the e oflset portion 11 of the lever12 so that the detent is-raised and the i arm 8 released when the lever12 rises.

When .the pressurein the boiler is much below the desired degree, as,1for example,

5 upon first starting the fire in the boiler, the '25 and the damper isheld wide open. As soon,

however, as the pressure in the operator engages the'arm 8 with thedetent,

ressure chamber 16 is suflicient to raise the ever 12 Qthe detent israisedand the arm 8 released,

in proportion to valiations of pressure in the .their'pivotal connectionthe and the force of the spring 6 is thenat once added, to that of thepressure chamber 16, so'

that the dam er is 'at once moved to close the smoke p1 e to asubstantial extent. Thereafter in t e operation of the mechanismthddamper is more or less closed gradually boiler. r

In order that themechanism may be ad- 1 justed to keep the pressure atany required degree thelever 12 is divided into two parts and the outerpart 12 is pivoted at 22 to the inner art 12* and is provided with anarcshape slotted portion 23. A binding screw 24 the end of the innerpart engages the curyed slot and seryes in adjusted relation.

to'maintain the parts By loosening the screw: and moving the partsrelatively about operation of the lever upon the damper may be eiiectedto vary'the pressure maintained by the mechanism.

'lhe alarm device hereinbefore referred to comprises an electric bell Z,connected, as

shown diagrammatically in Fig. 1., in circuit with a battery, the arm 8,and a fixed contact -26loeated in position to be engaged by the arm 8when the damper has been moved to fullyjclosed position. The sounding ofthis alarm warns the operator that the limit of draft-reduction has beenreached and that the fire is getting out of control of the automaticmechanism. The alarm device is also arranged to sound an alarm when thedamper 1s moved to wide-open position, to warn the o )erator that thefire requires attention. or this purpose the upright 20 on which thedetent is pivoted is insulated, and the detent and the arm 8 constitutecontact members in a circuit including the bell 25, as showndiagrammatically in Fig. 1. A switch 28 is arranged to connect the twocircuits alternately with the alarm according asit is desired to use theone or the other.

It is obvious that various modifications maybemade in the constructionshown and above particularly described within the nature and scope of myinvention.

I claim:

1. Automatic draft-controllin mechanism comprising, in combination wit aboiler, a draft-controlling device, means tending to move thedraft-controlling device to more or less operative-position in(proportion to the pressure. in the boiler, an vent such movement, saidmeans operating, upon the attainment of a predetermined pressure in theboiler, to disengage "the detent and release. the draft-controllingdevice.

2? Automatic draft-controlling mechanism comprising, in. combinationwith a boiler, a draft-controlling device, and, means controlled by thepressure in the boiler and constructed and operating, upon theattainment the draft, andupon further riseof pressure in the boiler, tomove the drcft-controlling device gradually to further reduce the draftin proportion to such rise.

.3. Automatic draft controllingmechanism comprising, incombination witha boiler, a draft controlling-device, a ressure chamber, and connectionsbetween t e pressure cham-- her and the draft-controlling devicecomprising a lever actuated by the pressure chamber and provided with anadjustable joint to adjustlthe connection between the pressurechamberand the (lraftcontrolling device.

In testimony whereof I have ailired my signature in presence of twowitnesses.

, GEORGE E. SCHUETZ. Witnesses:

BERNARD 'QowEN, WM. ASHLEY KELLY.

